No frequency on phase C of engine generator

[Kaydee]

Pls can someone advice on what to do if one of the engine generator phase is indicating low voltage and zero frequency, while others phases (A&B) indicate the correct voltage and frequency. The line contactor was replaced, the fuse at the upper electrical panel at FS 245 was ok, new generator installed, new voltage regulator was also  installed, yet the discrepancy persist. Kind help provide any assistance. Thanks

[n1dp]

Are you getting voltage at the generator terminals in the QEC?

 

[Kaydee]

Yes, there was voltage when the generator was on- line.. However, there is still no frequency and low voltage when the generator switch is in off position

[n1dp]

I guess I need to ask if these are the upgraded generator control panels where the "field trip" position on the generator switch is eliminated. If so, is it displaying a fault code?

[Kaydee]

I found that the output of the generator from the generator electrical box was not properly grounded to the engine. Cable ground repaired, system tested and found ok

[n1dp]

Good to hear. Was this found at the generator in the nacelle?